Nowadays, with the resources on the earth being depleted day by day, the cost of investment for energy increases significantly. Solar energy has drawn attention from the energy industry as an alternative source of energy, and found widespread applications in a variety of fields.
Solar cells convert photons from solar radiation into electrical energy through semiconductor equipment using solar cells (please refer to “Grown Junction GaAs Solar Cell” by C. C. Shen and G. L. Pearson, Volume 64, Issue 3, Proceedings of the IEEE, pages 384-385, March 1976.) The phototransducing process produces electron-hole pairs when the radiated photons reach a solar panel, combining the photons with atoms and valence electrons in the semiconductor material. Because of the electron-hole pairs, photovoltaic electromotive forces are formed close to the P-N junction, providing electrical power when P section and the N section in the semiconductor material are wired. Connecting the semiconductor materials parallel or in series provides a solar panel that outputs constant voltage and current.
To maximize reception of solar energy, the solar panel is normally in an elevated position and angled. This, combined with exposure to the elements, creates a need for frequent cleaning, especially since even a thin coating of dust or dirt can seriously affect the efficiency of photovoltaic energy production. Cleaning the solar panel is accordingly difficult. Existing cleaning devices for solar panels normally utilize mechanical structure, but still require manual operation. As well, such systems cannot detect contaminant on the surface of the solar panel in a timely manner, nor can they remove the dirt automatically. The cleaning device or system can thus significantly affect performance of the solar panel.